shafee



(No Model.)

i B' F SHAFBR. 2 Sheets-Sheet l. AUTOMATIC ELEGTRIOAL ANNUNGIATOR.

No. 422,981. y y Patented Mar. 11',` 1890.

(No Model.) 1 C 2 Sheets-Sheet 2.- B. P. SHAFER. AUTOMATIC ELECTRICALANNUNCIATOR.

Patented Mar. 11, 1890'.

L.. 8. 9.. 2` 2 4 C N INVENTDHI out.

UNITED STATES PATENT OFFICE. A

l BENJAMINFRANKLIN SHAFER, OF NEW YORK, N. Y.

AUTOMATIC ELECTRICAL ANUNCIATOR.

SPECIFICATION forming part of Letters Patent No. 422,981, dated March11, 1890.

Application filed January 10, `1889. Serial No. 296,026. (No model.)

To all whom it may concern:

4Be it known that I, BENJAMIN FRANKLIN SHAFER, a citizen of the UnitedStates, residing at New York city, in the county and State of New York,have invented certain new and useful Improvements in AutomaticElectrical Annunciators; and I do hereby declare the following to be afull, clear, and exact description of the invention, such as will enableothers skilled in the art towhich it appertains to make and use thesame.

My invention consists of a dial on which` the numbers are registered andaround which a rotating pointer is electrically impelled andautomatically stopped on the ,number corresponding with the room orother station from which the instrument is temporarily put in electricalconnection by the caller, all as hereinafter fully described, referencebeing made to the accompanying drawings, in which--` Figurel is a planview of my improved annnnciator with the inolosing-case removed andapart broken out. Fig. 2 is a sectional elevation on the line 2 2, Fig.l, and including' the inclosing-case, except a part that is broken Fig.3 is a plan View of the complete instrument on a reduced scale. Fig. 4is a detail representing a more concentrated arrangement of some of theparts.

The numbers of the rooms or stations to be called or announced areregistered at ot on the dial, consisting of the glass cover o1' front hof the inclosing-case b', with which a pointer c is arranged on arotating shaft CZ for traversing the register. The shaft has one or morecircuit making and breaking disks e, connected in circuit with the roomsor stations by a contact-brush f for each room or station, except whenbroken by the notch g of the disk, when the notch stands in the relationto the bearing-point of a brush to prevent contact. The shaft d also hasa ratchetwheel 71, of fine mesh, with which a springpawl t' engages toturn the shaft with its disks and pointer, said spring-pawl beingcarried on the free end of the armature-lever j, connected forcontinuous rapid vibration, while the magnet is energized by theelectric current, said magnet being in the circuit of the means in anyroom or station connected with the annunciator it will actuate thearmaturelever and the spring-pawl through the disk and the contact-brushcorresponding to that room and turn the pointer until the break of thecurrent by the notch of the disk coming to and breaking connection withsaid brush, when the pointer will stop at the number on the dial of theroom making the connection, and all the other brushes will remain incontact ready Vfor similar operation, said brushes and the notches, whenmore than one disk is used, being so adjusted on the shaft that only oneroom or station-circuit will be broken at any one time.

In Figs. 1 and 2 I have represented a separate disk for each room orstation circuit; but my invention is not limited to such arrange ment,for several rooms up to a considerable number may be connected throughone disk having only one break-notch, as indicated in Fig. 4, so thatone disk of large size and a short break-notch may serve for a largenumber of rooms, and thus the instrument will be simpler than with adisk for each room; but such arrangement may of course be employed whenpreferred. A bell k is also connected in the circuit to call attentionwhen the annunciator works, and when it happens that a second calloccurs from the same room While the circuit remains broken, through lackof change of the pointer by a call from any other room, the bellannounces the fact, the bell being connected in series with theinstrument, as shown in Fig. l.

The very rapid motion of the armature-lever enables the shifting of thepointer an entire revolution during the very short period of contact ofthe push-button, as it is commonly pressed.

The contrivance of pointer and dial forindicating the numbers is verymuch simpler and cheaper than the drop system, and it saves the troubleof readjusting the drops.

The spring-pawl is necessarily rather delicate in structure for the verysensitive action which the great rapidity of motion demands, and istherefore liable to undue vibration, from which I protect it to someextent by the prongs Z of a guard set up behind the bow of the pawl, sothat it plays forward and backward freely between said prongs, and isthere- IOO by prevented from such vibration. The pointer swings underorbehind the glass front b, which is thus enabled to be itted for adust-proof closure to the case for the protection of the Works,- and thecase can be kept closed, no drops or other thing about the instrumentrequiring; it to be opened or any part exposed to dust.

The pointer is made conspicuous to the view under the dial by being abroad lightcolored device with a dark-colored plate pbeloW Jforcontrast, and the glass dial is obscured by color or other means, exceptin the numbered divisions q, as indicated in Fig. 3, Where the pointerstops, and through which the pointer shows more distinctly for theobscurity of the rest of the dial.

I prefer to mount the pointer-carrying` arm s on its carrying-shaft dunder plate Q9, and make said arm with an offset at t, extending upthrough the annular slit u in the plate to support and carry the pointerabove the margin of said plate, and in such case Will'support thecentral part of said plate on the pointer-shaft either so as to revolvewith it or not, as preferred. In this case I represent said plateattached above the arm s by the screw and nut, Fig. 2.

What I claim, and desire to secure by Letters Patent, is-

The combination, with the magnet connected in the circuit of the variousrooms or stations, and the rapidly-vibrating armature-lever thereofhaving a spring-pawl, of the pointer-shaft and ratchet subject to theaction of said armature-lever and pawl, one or more notched disks onsaid pointer-shaft, and a series ot' contact making,` and breakingbrushes and bran ch lines connecting the several rooms or stations inthe order for breaking the connection of the branch lines individually,substantially as described.

In testimony whereof I affix my signature in presence of two witness.

BENJAMIN FRANKLIN SIIAFER.

'Vitnesses:

W. J. MORGAN, W. B. EARLL.

